Generally, as a method for joining walls of a housing of an electronic device such as a personal computer, there are known a method using screws and a method using claws protruding from one inner wall of a housing to be engaged in another wall (see, for example, Japanese Laid-open Patent Publications No. 05-315767 and No. 2000-59041).
Meanwhile, a housing of an electronic device is required not only to have its walls firmly joined together thereby reliably preventing the separation of the walls, but also to avoid such an inconvenience that a wall of the housing is warped by receiving an external force like a press on the wall by a user. Further, as for a housing of an electronic device expected to reduce the size and weight, such as a notebook personal computer and a mobile telephone, disconnection of walls and deformation of a wall due to an external force need to be prevented efficiently in a limited space.